Question

大家好，我需要帮助，我正在扑扑中跟踪应用程序，想要计算总高程增益。我从位置拉出高度，但无法在旅途中计算总高程增益，因此我将所有海拔值保存在列表中。基本上需要一个可以在旅途中提供总高程增益的公式。在颤动中像这样拉高

海拔= location.coords.altitude.toString（）;

Answer 1

请阅读以了解代码

我们正在比较三个高程点：

让我们以用户开始时的海拔高度为100m为例

三个标高，例如：700m，1000m，800。以上三个高程表明用户到达1000m后进行了下降。因此对于高程增益为1000-100m = 900m，这是真实的高程增益。减去的100m是行程开始时记录的海拔高度。

现在让我们考虑下三个高程为800m，600m，700m，这表明用户下降到600m后再次开始爬升。

所以现在真正的下降将是计算用户从1000m下降了多少，因此真正的下降将是1000m-600m = 400m

代码块中的注释解释了每个步骤的作用。

// This jut stimulates elevations in a small trip
  // instead of this list call the functions whenever you record a elevation.
  // and on the end of the trip call the [onStopTrip] function.
  List<double> listOfDemoElevations = [
    200.0, 300.0,400.0,1000.0,800.0,700.0,600.0,500.0,600.0,800.0,300.0,200.0];
  
  ///This Code Snippet compares Elevation of three points to see if the person has started ascending or is descending.
  /// Then the code only stores the point after which user asecded or descended.
  /// Then Calulates the total Elevation Gain or Elevation Loss.
  
  double elevationGain = 0.0;
  double elevationLoss = 0.0;
  double startTripElevation = 100.0; //Record the StartTripElevation;
  double previousElevation = startTripElevation;
  double beforePreviousElevation = startTripElevation;
  double adjustment =startTripElevation ; // this to get the truw ascend or descend

  
  // This function check the three elevation then adds to elevation gain or loss accordinly with adjustment so true elevation gain or loss is recorded.
  void calculateElevationGainLoss(double currentElevation) {
    if (beforePreviousElevation < previousElevation &&
        previousElevation > currentElevation) {
      elevationGain = elevationGain + (previousElevation - adjustment);
      adjustment = previousElevation;
    } else if (beforePreviousElevation > previousElevation &&
        currentElevation > previousElevation) {
      elevationLoss = elevationLoss + (adjustment - previousElevation);
      adjustment = previousElevation;
    }
    beforePreviousElevation = previousElevation;
    previousElevation = currentElevation;
  }

  /// this function check if the elevation at which the user ended the trip to be added to elevation gain or loss
  void onStopTrip(double currentElevation) {
    if (adjustment > currentElevation) {
      elevationLoss = elevationLoss + (adjustment - currentElevation);
    } else if (adjustment < currentElevation) {
      elevationGain = elevationGain + (currentElevation - adjustment);
    }

    
  }

  listOfDemoElevations.forEach((element) {
    calculateElevationGainLoss(element);
  });

  // Call this function when user hits end trip
  onStopTrip(listOfDemoElevations.last);

  print('Elevation gain=$elevationGain');
  print('Elevation loss=$elevationLoss');

您可以将整个代码放在dartpad中的void main{}中并进行测试：

如何从抖动中的gps高度计算海拔高度

1 个答案:

代码块中的注释解释了每个步骤的作用。